Answer:
From the list of options, Option A is the only correct one:
"the actual usage of materials was less than the standard allowed".
Step-by-step explanation:
Material usage variance
A material usage variance occurs when the standard quantity required to active a particular level of production is higher or lower than than the actual actual quantity used. A favorable variance would mean than less quantity of materials were used than the standard to achieve a given output level. And an adverse variance would mean the opposite.
Material price variance
A material price variance occurs where materials are purchased at a price either lower or higher than the standard price. A favorable variance is recorded where the actual total cost of materials is lower that the standard cost. While an adverse variance implies the opposite.
From the list of options, Option A is the only correct one